Caution: This is just a fun post.

I was performing some testing on Windows the other day and encountered the following error in the error log:

130313  9:40:03 [ERROR] Error writing file 'G:\mysql\log.txt' (errno: 28)

Quickly, I ran “perror 28″ from the command line:

c:\>perror 28
Win32 error code 28: The printer is out of paper.

Hehe, really, Windows?!?

In fact, the drive was out of space. No more could be written to the general log, hence the error.

Fwiw, the Linux OS code 28 reports what you would expect:

OS error code  28:  No space left on device

So, if you ever run into “The printer is out of paper” error, you’ll know what to do.

 

As some of you may or may not know, I’ve maintained a list of all InnoDB Plugin versions as they’ve historically contained a different version (entirely different numbering scheme) than the MySQL distribution they were included with.

This list was most helpful for troubleshooting various InnoDB issues when the plugin may (or may not) have been involved, and/or for benchmarking, etc. And it’s fair to say it was more useful when the InnoDB plugin was not the mainstream, which it is now.

However, with the latest releases, in MySQL and MariaDB, the “InnoDB Version” simply matches the “MySQL Version”. These “latest releases” include: MySQL 5.6.10, MySQL 5.5.30, MySQL 5.1.68, and MariaDB 5.5.30

Of course this isn’t the most newsworthy story, but having maintained this

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I just wrote an article about “Troubleshooting ‘Waiting for table metadata lock’ Errors for both MyISAM and InnoDB Tables” and then ran into a new, different metadata locking issue right after I posted it, and so I thought I’d share that too, just in case anyone ever encounters a similar situation.

In this case, mysqld kept crashing on restart, reporting “out of memory” errors:

/opt/app/mysql/product/mysql/bin//mysqld: Out of memory (Needed 840 bytes)
stack_bottom = 7fb4ebaeae58 thread_stack 0x40000
mysqld: /mysql/mysys/my_new.cc:52: int __cxa_pure_virtual():
  Assertion `! "Aborted: pure virtual method called."' failed.
mysqld: /mysql/mysys/my_new.cc:52: int __cxa_pure_virtual():
  Assertion `! "Aborted: pure virtual method called."' failed.
Fatal signal 6 while backtracing

There is a

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With the introduction of metadata locking in MySQL 5.5, it is much more common to see queries stuck in the “Waiting for table metadata lock” state.

If you see a query stuck in the “Waiting for table metadata lock” state, waiting for a MyISAM table, then it is because this table has been included as part of some uncommitted transaction (whether intentionally or not).

In fact, it could be as simple as issuing SET AUTOCOMMIT=0 followed by a SELECT against a MyISAM table (a transaction can be started 3 ways: START TRANSACTION, BEGIN, and SET AUTOCOMMIT=0). After that, the table will be locked to other DDL statements until the transaction is committed (or ended).

This metadata lock is meant for DDL statements, and so that is what it blocks. However, once a DDL

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Ever see an error like this in your console or error log, respectively, and wonder where it originated from?

Console (5.5.30):

ERROR 1017 (HY000): Can't find file:
'.\test\select@0020@002a@0020from@0020t1.frm' (errno: 22)

Error Log (5.5.30):

130307 23:22:04 [ERROR] C:\Program Files\MySQL\MySQL Server 5.5\bin\mysqld: 
Can't find file: '.\test\select@0020@002a@0020from@0020t1.frm' (errno: 22)

(Fwiw, they are harmless, unless it is indicative of some sql injection – but you may want to sanitize your data better, unless it’s just a one-time user error. Also, if you’re seeing it from the command line, then you’ll likely realize what you did immediately, and thus no need to ‘figure out’ what happened. However, when you *only* see this entry in the error log, and you want to know how that happened after the fact, then this is more

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The last MySQL User Group NL meeting was last Friday. It's always nice to learn about MySQL and meet other MySQL users. There were two presentations: one about MySQL User Defined Functions (UDF's) and one about MySQL TCO. The slides are available from the meetup page.

There are already a number of MySQL events announced for the next few months. I'll only list events in the Netherlands and Virtual events.

MySQL Virtual Developer Days
This is a virtual event which will take place on March 19 (EMEA region, NA event is on March 12). There are many interesting topics: Performance Schema, New 5.6 Features, Replication, MySQL Enterprise Monitor
The eVite

SkySQL and MariaDB roadshow
21 March 2013 in Amsterdam
This event  have









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It’s time to unveil the winners of the [Plus] readers choice awards!
Thank you again for your votes, remember that the real winner was the community, again.

I asked you to vote for what you used in 2012 and you’ve voted with your heart.
Here are the final results, congrats to the lucky guys and teams :

The most useful blogs in 2012 :

MySQL Performance Blog

The MariaDB Blog

SkySQL Blog

Ok, the Percona team members provides the best technical blog about MySQL (and more), this year again. Of course, this blog is very useful and interesting, I recommend to read the comments too, they are often very informative.

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February is turning out to be a busy month. I’ll be giving a talk about MariaDB at the SkySQL Solutions Day in Hamburg, alongside Sergei Golubchik. This happens February 1 2013.

I’ll also be in Brussels for FOSDEM and presenting at the MySQL & Friends devroom. Here I will talk about MHA and how you can get automated MySQL failover. I’ll also be hanging out at the CentOS booth with Karanbir Singh giving away MariaDB stickers all weekend. If you’re at FOSDEM, don’t forget to sign up for the

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SkySQL Roadshow is coming to Stockholm on Feb 7, come by and meet us. I'll be ending the day with a talk on Big Data, which will be a more generic Big Data talk with some MySQL relevance, but with the focus on Big Data in general.

I haven't blogging much recently, but that has some reasons. I am since Dec 1 the proud father of twins, a little boy and a little girl. I have yet to teahc them to write proper SQL, the have particular issues with subqueries, but we'll get there. In order to create the usual mess of things and to make sure things are at the brink of running out of control, we decided to renovate our flat in the middle of all this. But I'll get there, and once we have a new kitchen installed, I'll do some more blogging, I have some things piled up to write about.

/Karlsson

Oh yes, 2012 was an incredible year for the MySQL Community!
That’s why I would like to change the rules this year and I would like to offer you a new survey for this [Plus] reader’s choice 2012.

Community users, bloggers and events made the whole community last year, tell us how you used this community?
It will only take 5 minutes of your precious time, votes will be closed Jan. 31.

Vote for what you used! (with your heart, again…)

Note: There is a poll embedded within this post, please visit the site to participate in this post's poll. Note: There is a poll embedded within this post, please visit the site to participate in this post's poll. Note: There is a poll embedded within this post, please visit the site to participate in this post's poll. Note: There is a poll embedded within this post, please visit

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I think MariaDB has had a great few weeks recently and the timeline of these events are important.

27 November 2012 – WiredTree Adds MariaDB for Faster MySQL Database Performance (well worth reading their motivations to switch)

29 November 2012 – Monty Program & SkySQL release the MariaDB Client Library for C & Java

4 December 2012 – MariaDB Foundation is announced, see ZDNet coverage.

mid-December 2012 – Wikimedia Foundation starts migrating

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SkySQL is looking for a great Support Engineer to join our Team and work the APAC shift. This means you do not need to reside in APAC, but just want to work those hours.

If interested, there is a full description of the position here:

http://www.skysql.com/company/careers/skysql-support-engineer-apac

And as the post says, if you are interested, please send your resume/CV to careers@skysql.com.

Also, if you’d like, please feel free to ping me as well [chris at skysql dot com] and I can try to get your resume looked at with a higher priority (and feel free to ask me any questions too).

Happy Holidays!